import 'package:flutter/material.dart';

import 'animation_bottom_bar.dart';
import 'blank.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Animated Bottombar',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Animated Bottombar'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with  TickerProviderStateMixin {
  int _counter = 0;
  int _selectedBarIndex = 0 ;
  TabController _tabController ;
  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  void initState() {
    super.initState();
    _tabController= TabController(length: listBarItems.length, vsync: this);
    _tabController.addListener((){
      print(_tabController.index);
      dragTabView(_tabController.index);
    });
  }

  @override
  void dispose() {
   _tabController.dispose();
    super.dispose();
  }

  void dragTabView(int index){
    setState(() {
      _selectedBarIndex = index;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
        appBar: AppBar(
          // Here we take the value from the MyHomePage object that was created by
          // the App.build method, and use it to set our appbar title.
          title: Text(widget.title),
        ),
        bottomNavigationBar: AnimatedBottomBar(
            barItems: listBarItems,selectedBarIndex: _selectedBarIndex, onBarTap: (item) {
            print("${item.text} ${listBarItems.indexOf(item)}");
            _tabController.index = listBarItems.indexOf(item);
        }),
        body: TabBarView(
            controller: _tabController,
            children: listBarItems.map((item) {
              return Center(child: Text(item.text));
            }).toList()
        ));
  }
}

//菜单按钮
List<BarItem> listBarItems = [
  BarItem(text: '首页',iconData: Icons.home,color: Colors.blue[400]),
  BarItem(text: '订单',iconData: Icons.reorder,color: Colors.amberAccent[400]),
  BarItem(text: '购物车',iconData: Icons.shopping_cart,color: Colors.red[400]),
  BarItem(text: '收藏',iconData: Icons.favorite,color: Colors.green[400]),
  BarItem(text: '我的',iconData: Icons.person,color: Colors.black54)
];

